序列的操作详解
1序列基本操作：
#!/usr/bin/env python # encoding: utf-8 #________________________________________________序列基础操作________________________________________________________________ classmates = ['Michael', 'Bob', 'Tracy','chen','chen','chen'] # 末尾追加元素 classmates.append('Adam') print('追加后',classmates) # 指定插入位置 classmates.insert(1,'Jack') print ('指定位置插入后',classmates) ###删除指定元素(根据下标) classmates.pop(1) print('删除指定元素后',classmates) # 删除指定元素(根据指定元素) classmates.remove('Tracy') print('删除指定元素后',classmates) #删除序列下标元素 del classmates[1] print('删除指定元素后',classmates) #修改指定元素 classmates[1]='test001' print ('修改指定元素后',classmates) #index是查看元素的下标 print('先查看list',classmates) print(classmates.index("chen")) #统计元素出现的次数 print(classmates.count('chen')) ##########排序######################## print('排序前',classmates) classmates.sort()#顺序 print('排序后',classmates) # #日期排序操作 dict_key=['2022-03-10', '2022-03-13', '2022-03-14', '2022-03-15', '2022-03-16'] classmates.sort(reverse = True)#倒序 print(dict_key) #备注char类型不能联合int使用 #两个list拼接 a=[11,12,13] b=['name','age'] c=a+b print('两个list拼接',c) ###______________________________________________________切片操作______________________________________________________________ w = ['Michael', 'Sarah', 'Tracy', 'Bob', 'Jack','chen','dalan','abb'] print(w[2])#获取第2个元素 print(w[1:-2])#获取1到倒数第2个 print(w[2:4])#获取2到4个元素 print(w[-3:])#获取后3个元素 print(w[-3])#获取倒数第3个元素 print(w[:-3])#获取元素、排除后3个元素 print(w[::-1])#倒序显示序列 print(w[::-2])#-2为步值，表示倒序 并隔2取值 print(w[:1:-2])#-2为步值，表示倒序 并隔2取值(到1就停止)) ###________________________________________________list其他基础用法_______________________________________________________________________ a=[5,3,9,12,7] b=[3,6,6,3,7,4,2] ###统计list元素的和(用于list元素为int类型) print("list元素累加&求和(int类型):",sum(a)) ###list去重操作 print("list去重:",list(set(b))) ###list的append追加(append方法用于追加单个元素,当追加一个列表时 会当作一个元素嵌套) c=[1,2,3];d=[1,2] c.append(a)#追加一个列表到c d.append("32") #追加一个元素到d print("追加一个列表后打印c:",c) print("追加一个元素后打印d:",d) ###list的extend追加(用于追加一个可迭代对象的元素) e=[1,2,3] e.extend(a)#它会将列表中的每个元素都添加到目标列表中，而不会将整个列表作为一个元素添加。 print(e)
2.迭代器转数据类型：
dalan='hdhdwhdwe' #______迭代器转换______________________ print(type(iter(dalan))) print(type(dalan.__iter__()))
3.list拆分在组装：
#_________________________________把list按分号拆分在形成list_______________________________________________________ aa11=['assets/game/resource/shj_assets/picture/bigbg/create_role_bg1_ed9d9ee8.png;assets/game/resource/shj_assets/picture/bigbg/create_role_bg2_fc4b58f.png','assets/game/resource/loginres/login_bg_f_44ae01ef.jpg','333333'] cc=[] for aa in aa11: bb= aa.split(';') if ';' in aa else aa.split() cc+=bb #print(cc)打印每次累加 #打印最终结果 print(cc) #___________________________________________________1累加到100的和_______________________________________ coun=0 for i in range(1,101): coun+=i print(coun)
4.列表组合
#!/usr/bin/python # -*- coding: UTF-8 -*- ###____________________字符串组合成list(不重复)__________________________________ def perms(s=''): if len(s) <= 1: # 长度为1的字符串，排列组合就是自己 return [s] sl = [] # 放结果 for i in range(len(s)): # 第一个数的可能取值 for j in perms(s[0:i] + s[i + 1:]): # 排除第一个数 sl.append(s[i] + j) return (list(set(sl))) perm_nums = perms('123') print('字符串组合结果：', len(perm_nums), perm_nums) ###______________________字符字符串组合成list(不重复）______________________________ '''perm和上面perms区别,转成了int类型，列表元素也是int''' def perm(s=""): if len(s) <= 1: return [s] else: s1 = [] for i in range(len(s)): for j in perm(s[0:i] + s[i + 1:]): s1.append(s[i] + j[:2]) return (list(set(s1))) perm_num = perm("123") m = list(map(int, perm_num)) # map函数把list中的字符串转化成int print(len(perm_num), m) #_________________________一个列表组合成多个列表(方法一)___________________________ '''http://www.360doc6.net/wxarticlenew/882598242.html''' def list_name(name): result=[] for i in name: for j in name: for k in name: if len(set((i,j,k)))==len(name): result.append([i,j,k]) return result num_list=[1,2,3] res=list_name(num_list) print(f"列表组合组合方法一:{res}") #_________________________一个列表组合成多个列表(方法二)___________________________ #encoding =utf-8 num_list = [1,2,3] def permute(nums): from itertools import permutations result = [] for i in permutations(nums,len(nums)): result.append(list(i)) return result print('列表组合方法二:',permute(num_list)) #____________________________一个列表组合成多个列表(方法三)__________________________ import string num_list = [1,2,3] length = len(num_list) var = tuple([string.ascii_lowercase[i] for i in range(length)])#生成字母代表的变量序列 temp = "["+','.join(var)+"]" result = eval("["+temp+''.join(['for %s in num_list '%i for i in ''.join(var)])+'if len(set(%s))==3'%temp+"]") print('列表组合方法三:',result) #____________________________一个列表组合成多个列表(方法四)__________________________ #encoding =utf-8 num_list = [1,2,3] def permute(nums): from functools import reduce result = [list(i) for i in reduce(lambda x,y:[str(a)+str(b) for a in x for b in y if str(b) not in str(a) ],[nums]*len(nums))] return result print('列表组合以字符串方式：',permute(num_list))
5.列表去重&两列表筛选
#!/usr/bin/python # -*- coding: UTF-8 -*- #_____________在两个列表都存在的元素________________________ list1 = [1, 2, 3, 4,"kill","kiss",5,"chenwei"] list2 = [4, 5, 6,"test","ppp", 7, 8,"chenwei"] common_elements = [x for x in set(list1) if x in list2] print("两个列表同时存在的元素:",common_elements) #_____________在list1存在,list2不存在的元素_________________ list1 = [1, 2, 3, 4,"kill","kiss",5,"chenwei"] list2 = [4, 5, 6,"test","ppp", 7, 8,"chenwei"] result = [x for x in list1 if x not in list2] print("在list1存在,list2不存在的元素:",result) #_____________在list1不存在，list2存在的元素_________________ list1 = [1, 2, 3, 4,"kill","kiss",5,"chenwei"] list2 = [4, 5, 6,"test","ppp", 7, 8,"chenwei"] result = [x for x in list2 if x not in list1] print("在list1不存在,list2存在的元素:",result) #__________________列表去重________________________________ test=[2,8,"test1",8,"chen","hallo word","test1"] print("转为集合:",set(test)) print("先转集合去重，在转成list:",list(set(test)))
6.list过滤处理
###_____________________________过滤list中指定的元素_____________________________________ s=['2022-03-09', '2022-03-10', '2022-03-14', '2022-03-14','', '', '\n','chen','2022-03-15'] #过滤list为“”的元素 comp = [x for x in s if x != ''] print("过滤list的空白字符",comp) ###过滤list为 空白&chen&\n的元素 chen_list = [x for x in s if x != '' if x !="chen" if x !='\n'] print("过滤list为 空白&chen&\\n的元素",chen_list) ###list去重操作 list_set=list(set(s)) print("通过集合去重:",list_set) ###______________________________判断list是否为空__________________________________________ cc=['abc','chenwei',''] ##方式一 if len(cc): print('cc不为空') else: print('cc为空') ###方式二 if cc: print('cc不为空') else: print('cc为空') ###方式三(判断list所有元素是否有空) if all(cc): print('全部元素不为空时，结果Ture') else: print('有任何一个元素为空，结果为False')
###方式四:
my_list = []
if bool(my_list) == False:
print("列表为空") ###______________________________判断两个list是否相等_______________________________________ ###案例一(jieguo等于true表示相等) aa=['chenwei','chen'] bb=['chenwei','chen'] cc=['chen','chenwei'] jieguo=aa==bb print(jieguo) ###案例二(需要 import operator ) # print(operator.eq(aa,bb)) ###案例三 (需要顺序相同) if aa == bb: print("两个list相等(需要list顺序相同)") else: print("两个list不相等") #方案四 (元素顺序不同也可判断) if sorted(aa) == sorted(cc): print("两个list相同(元素顺序不同也可判断)") else: print("两个list不相同") ###__________________________过滤list元素里的字符,然后拆分____________________________________________ All_Package=['package:com.chen.cn\n','package:com1234.cn\n'] name=[''.join([i for i in price.replace("package:",'').split('\n')]) for price in All_Package] print(name) ###列表解析式： list=['package:com.crd_cn\n', 'package:com.555ap\n', 'package:com.mi.shop\n'] print([''.join([i for i in price.replace("package:",'').split('\n')]) for price in list]) ###普通方式： aaa=[] for i in list: aaa.append(i.replace("package:",'').strip('\n'))#先指定字符删除，然后去掉末尾换行，再追加到list print(aaa) #______________________________过滤嵌套list元素______________________________________________ aaa=[{'项目': 'QQ', '用例编号': 'test_001', '用例名称': '获取QQ号'}, {'项目': '小飞机', '用例编号': 'test_002', '用例名称': '登录平台'}, {'项目': '小飞机', '用例编号': 'test_003', '用例名称': '登录平台'}] print("查看list元素数:",len(aaa)) #过滤掉"用例编号"不等于”test_003“的元素 bbbb = [item for item in aaa if item.get('用例编号') != 'test_003'] print("过滤掉用例编号不等于test_003的元素:",bbbb)
7列表转字典
##_______________________________________两个普通列表转字典________________________________________________________ aa=["name","age","sehngao"] bb=["张三",25,"163cm"] #方式一通过zip: dict1=dict(zip(aa,bb)) print("两个列表转字典",dict1) #方式二通过循环 result = {} for i in range(len(aa)): result[aa[i]] = bb[i] print("转换后的字典",result) ##______________________________________二维数组转字典_____________________________________________________________ my_list = [("a", 1), ("b", 2), ("c", 3)] #方式一 强转换 my_dict = dict(my_list) print("转换后字典",my_dict) #方式二循环转换 my_dict = {key: value for key, value in my_list} print("转换后字典11",my_dict)
8.列表中级操作
#__________________________________________________序列中级操作__________________________________________________________________ #判断list包含某个元素 names1=["Alice","Linda","Bob"] if "Alice" in names1: print(True) else: print(False) #判断list包含某个元素(使用三元表达式) res=["Alice","Linda","Bob"] boj= True if "Alice" in res else False print(boj) #list是否包含某个字符串 abc=['chen','chenwei','www','wedd'] a3 = [i for i in abc if 'chen' in i] print('包含chen的元素有',a3) #两种获取字符串的方式 a='python' c=len(a) for letter in range(c): # 第一种方式 print ('当前字母..... :', a[letter]) for letter in a: # 第二种方式 print ('当前字母 :', letter) #序列、元组拼接 chen=('wei','haha',26,'nini',77) print (chen) wei=('tata',22,'nini') chenwei=chen+wei #元组连接,列表也可以连接 print (chenwei) #_____________________________________________________遍历_______________________________________________________________________ #字典遍历(转成list) dic = {'tom':11, 'sam':57,'lily':100} for (key,value) in dic.items(): print("这是key:" , key) print("这是key的value:" ,value) #序列遍历方式1 fruits = ['banana', 'apple', 'mango','mangao'] for x in fruits: print ('当前水果 :', x) print ("Good bye!") #序列遍历方式2 fruits = ['banana', 'apple', 'mango','mangao'] a=len(fruits) for b in range(a): print(fruits[b]) #___________________________________________________列表解析______________________________________________________________________ aaa=[a for a in range(1,10)]#序列解析 print (aaa) #在1-10中求出大于4的平方(列表生成方式_) oo=[i**2 for i in range(1,11) if i>=4]#通过列表解析求出 print (oo) #在1-10中求出大于4的平方(普通模式) L = [] for i in range(1,11):#普通序列求出 if i >= 4: L.append(i**2) print(L) #生成1到10的list（列表生成方式_） chen=list(range(1, 11))#第一种 print(chen) #生成1到10的list(普通模式) k=[] for i in range(1,11):#第二种 k.append(i) print(k)
9.二维列表&一维列表转换及操作
备注：二维列表又称嵌套列表，列表也可以叫数组
#_______________________________________________________二维数组__________________________________________________________________ #....................二维数组(嵌套list) 转一维数组............... wei=(('2022-03-13', 29), ('2022-03-14', 22), ('2022-03-15', 21), ('2022-03-16', 18)) list1 = [i[0] for i in wei] list2 = [i[1] for i in wei] print('嵌套list转普通list',list1) print('嵌套list转普通list',list2) #..................二维数组(获取指定数组或元素)................... L = [ ['Apple', 'Google', 'Microsoft'], ['Java', 'Python', 'Ruby', 'PHP'], ['Adam', 'Bart', 'Lisa'] ] print("获取第2个列表：",L[2]) print ("获取第2个列表第0个元素：",L[2][0]) #...........遍历二维数组& 把二维转成一维数组.................... L = [ ['Apple', 'Google', 'Microsoft'], ['Java', 'Python', 'Ruby', 'PHP'], ['Adam', 'Bart', 'Lisa'] ] sum_list = [] for i in range(len(L)): for j in range(len(L[i])): print(L[i][j]) sum_list.append(L[i][j]) print("遍历后一维list", sum_list) #...................两个list转成二维list/嵌套list................... '''append:用于追加单个元素, 追加整个列表会嵌套 extend用于最近整个列表不会嵌套, 追加单个字符串会被拆分 ''' #append以嵌套方式插入(一个元素时就不会嵌套) aa=['name','age','shengao'] bb=["张三",25,"170cm"] aa.append(['chen','1234']) #aa.append('1234')#单元素追加，不会嵌套 print("嵌套方式追加",aa) #extend追加不会嵌套 aa1=['name','age','shengao'] bb1=["张三",25,"170cm"] bb1.extend(aa1) print("追加整个列表不会嵌套",bb1)
相关连接：
https://www.jianshu.com/p/6caf8215a5b1 .........................................................三维数组
